The present invention generally relates to cooling systems, and more particularly, to cooling a motor with a fan.
A fundamental requirement of the cooling of an electric machine may be the required removal of heat so that the temperature distribution resulting from the losses associated with the energy conversion does not result in component temperatures that exceed a component thermal capability. Temperature distribution may vary with the operating conditions of the motor, duty cycle, and environmental conditions including active cooling. Cooling can be addressed with passive and active cooling methods. Passive cooling may include natural convection, radiation, and thermal conduction to a mounting structure. Active cooling may include forced air and forced fluid cooling. Active cooling can be applied to the internal components and external structure of the electric machine.
Installations typical to aerospace and transportation applications may require coordinated packaging and layout of the machine to the space and envelope restrictions of the vehicle. In this architecture, the fan may be shaft mounted. Nonetheless, whether the fan is electrically or mechanically driven, axial space may be consumed by the fan and therefore may not be available for an electric machine. When a fan is radially mounted, cooling fins may still be required to increase the heat transfer surface to air flow and distribute the airflow to the desired locations for a uniform heat removal. Conventional radially mounted fans may cool in one direction. This may result in inefficiencies due to non-uniform cooling of sides of a motor.
As can be seen, there is a need for a multidirectional air cooling of a motor using a radially mounted fan.